Perseids: guide to enjoy the tears of San Lorenzo, the night with the most shooting stars

Observing the Perseids, one of the most anticipated astronomical spectacles of the summer, does not require NASA instruments or any scientific knowledge: just get away from the light pollution of large cities, stop looking at the mobile for about 10 minutes so that the view adapts to the darkness and delight in contemplating the night sky. "One thing we recommend is to see the shower of stars lying on some horizontal surface, that when you stand for a long time looking up you end up with the fatal cervical," jokes astrophysicist Javier Armentia, director of the Pamplona Planetarium astronomical observatory, in the capital of Navarre.

From the second half of July until the end of August, there is this shower of stars, also known as the Perseids. Specifically, the maximum to see the astroshow is the early hours of the night of August 12 to 13, as reported by the Institute of Astrophysics of the Canary Islands (IAC). This cosmic phenomenon, where more particles can be seen colliding with the Earth's atmosphere than usual, has its origin in the 26-kilometer-wide comet 109P/Swift-Tuttle, discovered in 1862, as explained by astrophysicist Pablo Pérez González, from the Center for Astrobiology of the CSIC. And he adds: "the Moon will be in the waning quarter on that date, the new moon is on August 16, so 2023 will be very conducive to seeing the great summer meteor shower."

The Perseids are the gas and solid particles that break off from the comet's tail in each of its orbits around the Sun every 133 years. When Earth enters the dust cloud that the comet leaves as a trail in space, the particles that enter the Earth's atmosphere are the summer meteor shower. Particles sometimes as small as a grain of sand that, due to the impact with the atmosphere so abrupt and the high temperature in fractions of a second, disintegrate and their flash is what can be observed.

Learn moreWhat the meteor shower tells us about our origins and our future | Cosmic vacuum

Given the optimal conditions in terms of darkness and clarity of the sky, an average citizen can see an average of 50 to 100 shooting stars per hour, says Armentia. "It is the night of the year that more stars are going to be seen, there are people who expect a continuous downpour," clarifies the director, "but the right attitude to see them is to be surprised, those few that you can see at the moment you look at the sky is already wonderful. "

It is the night of the year with more shooting stars; There are people who expect a continuous downpour, but the right attitude is to be surprised

Javier Armentia, astrophysicist and director of the Pamplona Planetarium

As every summer, Armentia organizes a scientific popularization event, which this year will be in the town of Puente de la Reina, a municipality 20 minutes from the capital of Pamplona. The town has collaborated with the scientists of the observatory in the installation of lighting network that does not project upwards, so that it is as sustainable as possible and less in conflict with the night, what are known as "areas of special protection of the night sky", details the scientist.

The initiative is part of the Starlight Foundation project that was launched in La Palma by the IAC in 2007. The least populated Spain has "a potential worth claiming" in the fight against light pollution, says the astrophysicist: "Empty Spain is the one with the best sky, something that for the observation of the stars becomes a value".

The night brightness grows by 10% per year, the composition shows the sky in different terrestrial environments according to light pollution. NOIRLab/NSF/AURA, P. Marenfeld

Darkness is the best recommendation not to miss the celestial spectacle. Hence, Armentia joins the criticism against the proliferation of light pollution in recent decades in cities and their surroundings, as well as the increase of private satellites in orbit that hinder scientific work and observation. For the astrophysicist this has been a clear setback: "Since the 90s the quality of the sky has worsened; even to be able to see the Milky Way, people who are already an age remember when we went to the village, but you ask the little kids in the planetarium, they tell us no."

A type of pollution that disrupts animal life, which also includes human health, as constant light exposure alters people's circadian rhythm and gut microbiome. "We do not proselytize, but the truth is that it is a great opportunity to take advantage of the Perseids to talk about how beautiful the night sky is," concludes the director of the observatory.

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